• Global protein market expected to be worth £25bn by 2028, figures show

Once the preserve of bodybuilders looking to bulk up, protein shakes have recently grown in popularity, even among those who will never see the inside of a gym.

Figures released in May showed the global protein market will be worth £25bn by 2028 – up from £16bn in 2021, while in the UK 7% of Britons – and 39% of those who exercised more than once a week – used sports nutrition products such as protein shakesaccording to Mintel research in 2017.

Some use these products in the belief that they will help build muscle (although experts say they won’t without exercise), others as a way to improve their diet. But questions hang over them: what benefit do they really bringfor example, and do they have to carry a health warning?

This was suggested by a coroner during the recent inquest into the death of Rohan Godhania, 16, from Ealing, west London. He fell ill after drinking a protein shake on August 15, 2020 and tragically died three days later after suffering “irreversible brain damage”.

The shake caused a rare genetic condition, ornithine transcarbamylase (OTC) deficiency, which prevents the breakdown of ammonia (a byproduct of protein breakdown). This causes ammonia to build up to lethal levels in the bloodstream, leading to brain swelling.

Coroner Tom Osborne told the inquest: “My preliminary opinion on them is that I should write to one of the regulators that some sort of warning should be put on the packaging of these drinks because, although OTC is a rare condition, it can have harmful effects if someone drinks [one].’

There is no doubt that protein is vital for good health. The body breaks it down into amino acids needed to build muscle and cells.

Protein is also essential for the proper functioning of the immune system. But it’s readily available in many foods, and most people get enough of it (men need about 56g a day and women need about 46g a day), including vegetarians and vegans. For example, there are approximately 34g of protein in a 140g serving of farmed salmon, 5.7g in 100g of Greek yogurt, plus 28g in a 100g can of tuna.

Protein powders – which you mix with milk or water – or ready-to-drink versions typically contain 20-30g of protein per serving. Many also contain creatine, a supplement that can improve performance and increase muscle mass by promoting water absorption in the muscles, as well as vitamins, minerals and flavorings.

While it’s always best to get nutrients from food, protein shakes have their uses, according to registered dietitian Priya Tew.

“Protein shakes can be helpful for those who exercise a lot, such as professional athletes, and those with additional protein needs, including those with poor appetites or struggling with illness,” she says. . Another group that could benefit is the over-65s, as studies like this from the University of Sheffield in 2020 suggest that up to 85% don’t get enough protein.

“We often see a decline in muscle mass and strength as people age, which can impact their physical function and affect their health,” says Marcela Fiuza, registered dietitian specializing in metabolic health and aging. . “Although many older people can get adequate amounts of protein from their diets, some struggle. Many older people, especially those over 70, do not consume the minimum protein requirements, so a protein supplement may be helpful.

Indeed, the dietary protein needs of the elderly have recently been revised upwards by the Prot-Age Study Group, an international organization commissioned by the European Society of Geriatric Medicine.

The new recommendations are that healthy people over 65 should now consume 1-1.2g of protein per pound of body weight; it could be higher for sick people.

But can you have too much of a good thing?

“Protein is a complex molecule,” says Linia Patel, a London-based sports dietitian and spokesperson for the British Dietetic Association.

“So for the body to break it down into amino acids, your liver and kidneys have to do a lot of work.

“It’s not a problem if you have a healthy liver and kidneys, but it could cause problems if you have liver or kidney disease. You may need to limit your protein intake to prevent damage to these organs.

Those who choose to take protein shakes have several choices to choose from, which vary in quality, price, and ingredients.

Some have high levels of protein, sugar and salt, as well as a range of additives including preservatives. “As a general rule, go for products with minimal ingredients,” says Linia Patel.

‘Ideally, you should also choose a protein powder with less than 5g of sugar per serving. [especially if your goal is fat loss or better overall health],’ she says. “I’m a big fan of unflavored protein powders because they have no added sugar or sweeteners.”